Seems Chicago Bulls star Jimmy Butler has made an off-season acquisition of his own … ’cause he was out on a lunch date with “Pretty Little Liars” star Shay Mitchell — and we’re told the two are together.

Butler and Mitchell had lunch together at Il Pastaio in Beverly Hills on Saturday — and TMZ Sports has video of the two smiling and laughing together after the meal.

Sources extremely close to the couple tell us it wasn’t just a one-off lunch thing — the two are dating … but it’s pretty fresh, so they’re keeping things on the DL.

Later that night, Butler was out at dinner without Shay — and was playing it coy when we asked about the relationship … but you can tell.

We also asked if there was ever a chance of him playing for the Lakers — but Butler made it clear he’s a Bulls man.